Updated April 2026 · Reviewed by Cory Salisbury, Construction Financial Specialist
You've got $400K in signed contracts and $12K in the bank. Your payroll is due Friday. Sound familiar?
Here's the quick answer: Construction cash flow forecasting projects your incoming revenue (draws, retention releases, progress billings) against outgoing obligations (payroll, subs, materials, loan payments) across a rolling 13-week window. Salisbury Bookkeeping builds and maintains these forecasts for contractors earning $500K–$10M, updating weekly so you always know when cash is tight and can act before it's a crisis.
You could be winning work and still unable to make payroll. This isn't a reflection of your profitability—it's the brutal geometry of construction timing.
Result: You're funding the entire project from your working capital while waiting for payment. One slow GC or material price spike and you're frozen.
A $2M project can be 25% profitable on your income statement and still trigger a cash crisis. Your accountant sees net income. Your bank account sees zero dollars on Friday morning.
Without visibility into that 13-week window, you're flying blind. You make payroll decisions based on last month's bank balance, not next month's reality.
A 13-week cash flow forecast is a week-by-week projection of cash inflows (draws, retainage releases, change order billings) and outflows (payroll, sub payments, material purchases, debt service, overhead) for the next three months.
Unlike static budget forecasts, the 13-week forecast is living and updated weekly with actual schedule changes, payment delays, and newly awarded work. Each week, the oldest week drops off the back and a new week is added to the front—always maintaining a 13-week rolling window.
Salisbury Bookkeeping builds your 13-week forecast from your actual operational data. Here's the process:
You provide (or we pull from your project management software) actual payroll totals, material invoices, sub payments, and invoice collection dates. We add upcoming known obligations: loan payments, tax deposits, equipment purchases.
We sync your forecast with your GC's draw schedule. We know when your progress invoices are due, when the GC typically pays (or delays), and when retainage gets released. No surprises.
The forecast calculates your starting cash balance week-by-week, subtracts outflows, adds inflows, and shows your projected ending balance for each of the next 13 weeks. You see exactly when you're tight.
Want to know what happens if a payment is delayed 2 weeks? Or you land a new project that starts in week 4? We build scenarios: delayed payment, new project start, material price increase, payroll spike. You see the impact before it happens.
A simple, color-coded dashboard showing week-by-week projections:
| Week | Starting Balance | Inflows | Outflows | Ending Balance | Status |
|---|---|---|---|---|---|
| Week 1 | $45,200 | $22,000 | $18,500 | $48,700 | Safe |
| Week 2 | $48,700 | $0 | $19,200 | $29,500 | Safe |
| Week 3 | $29,500 | $0 | $28,900 | $600 | Tight |
| Week 4 | $600 | $35,000 | $18,750 | $16,850 | Tight |
| Week 5 | $16,850 | $0 | $15,200 | $1,650 | Tight |
| Week 6 | $1,650 | $0 | $22,500 | ($20,850) | Crisis |
| Week 7 | ($20,850) | $45,000 | $18,200 | $5,950 | Safe |
Notice Week 6? That's your signal to call the GC about accelerating the draw, defer a material purchase, or arrange a short-term line of credit. You're not scrambling on Thursday—you're planning on Monday.
The forecast isn't a report you file away. It's a decision engine. Here's how contractors use it:
You see Week 6 is tight. On Monday of Week 5, you call your GC and ask for the draw 3 days early. Or you know you need a $25K line of credit to bridge the gap. No surprises Friday afternoon.
Steel prices are dropping and you want to buy 8 weeks of stock. The forecast shows you'll have $65K available in Week 3. You buy. If it showed $12K, you don't. Data-driven purchasing instead of hope.
You're negotiating a line of credit and the lender asks what monthly debt service you can handle. You show them the 13-week forecast and say confidently: "I can do $8K/month without stress." No guessing.
A $800K project lands on your desk. You run the scenario: "If we start this in 6 weeks, what's our cash position?" The forecast shows you can fund the labor and material without a loan. You bid it. Without the forecast, you pass.
Every week. We pull your latest payroll, invoices, collections, and known obligations—then rebuild the 13-week projection. You always have current data, not last month's assumptions.
That's expected. We build the forecast from your actual weekly data, so schedule changes flow into the projection automatically. When your GC delays a draw or you push back a material delivery, the forecast reflects it next week.
Not necessarily. If you use QuickBooks, Xero, or a construction PM platform (Procore, Touchplan), we can pull data automatically. If you're spreadsheet-based, we build the forecast from whatever data you provide. Either way works.
Perfect. The forecast aggregates across all projects—so you see your total cash position, but you can also drill into individual project timing to understand where tightness is coming from. Multi-project contractors are actually our ideal clients.
We price based on your revenue and complexity. Most contractors earning $500K–$10M pay between $200–$500/month for ongoing forecast maintenance and scenario modeling. It pays for itself the first time you avoid a cash crisis or negotiate better payment terms.
Not directly, but the 13-week forecast is exactly what banks want to see when you're applying for a line of credit. We help you present it. Many lenders see a solid forecast and approve faster—and at better rates—because you've shown you understand your cash cycle.